Heavily tattooed, Sinclair sat in silence as the court was told of his actions at MIePLACE nightclub in the early hours of April 16.

Police prosecutor Gavin Reece said Sinclair was heavily intoxicated when he approached the victim, a 23-year-old man dancing with his girlfriend, and pushed him from behind without warning.

The victim fell forward into other dancers before turning around and asking "What are you doing?"

He then turned back to his girlfriend and continued dancing when, without warning, Sinclair punched him in the mouth with such force the man fell to the floor and his upper left front tooth was knocked out.

Bleeding from the gums, the victim managed to find his tooth on the dance floor and left for hospital with the assistance of his girlfriend.

Sinclair later became engaged in another scuffle with security staff, for which he was convicted of committing a public nuisance at an earlier hearing.

Asking for a two-year sentence for the assault, Mr Reece submitted Sinclair's extensive history of violent and drug-related offences to Magistrate Melanie Ho.

He also submitted a photo of the damage to the victim's face, an ongoing treatment plan, and a victim impact statement.

The court heard the victim's front teeth were loose and he was still experiencing pain and swelling in his face, as well as having to undergo ongoing root canal treatment as a result of the attack.

He was not able to eat his normal diet, and a split to the inside of his lip left him unable to drink properly without a straw, the statement said.

The victim suffered ongoing anxiety and depression and was self-conscious about the fibreglass fitting helping him keep his tooth in place.

He has since moved to New South Wales so his mother can assist him in his recuperation.

Defence lawyer Cassandra Ditchfield said her client had been "on a downward slope" since the death of his father in November. Ms Ditchfield said Sinclair had been under strict bail conditions when his father had passed away, and his request to police for him to be able to travel to his father's funeral had been denied.

She said it was from that point he had begun "drinking himself into oblivion", and he believed his issues to do with violence "really only occurred when he was intoxicated".

Ms Ditchfield asked Ms Ho to consider an 18-month sentence instead of the prosecution's suggestion of two years, as her client had made efforts to rehabilitate himself with anger management and alcohol courses while in prison.

"There haven't been any spots available in courses that have been running... he's on the list for any and all relevant courses for the foreseeable future," she told the court.

She said Sinclair's epilepsy left him "particularly vulnerable in prison", and said he was experiencing seizures roughly every two weeks.

Her client also missed his 15-year-old son competing in Barcelona for the International Scooter Association World Championship, which she acknowledged was "an extra unusual impact" of her client's ongoing custody.

Magistrate Melanie Ho took into account Sinclair's efforts at rehabilitation, but said the public needed to be protected from people who committed "gratuitous acts of violence".

She said Sinclair's history of violent offences across Queensland and New South Wales "did not speak well" of him.

Ms Ho sentenced Sinclair to 18 months in prison, with a parole release date of November 16.